Flexibility and plasticity of human centrin 2 binding to the xeroderma pigmentosum group C protein (XPC) from nuclear excision repair.Yang, A., Miron, S., Mouawad, L., Duchambon, P., Blouquit, Y., Craescu, C.T.
(2006) Biochemistry 45: 3653-3663
- PubMed: 16533048
- DOI: 10.1021/bi0524868
- PubMed Abstract:
Human centrin 2 is a component of the nucleotide excision repair system, as a subunit of the heterotrimer including xeroderma pigmentosum group C protein (XPC) and hHR23B. The C-terminal domain of centrin (C-HsCen2) binds strongly a peptide from the ...
Human centrin 2 is a component of the nucleotide excision repair system, as a subunit of the heterotrimer including xeroderma pigmentosum group C protein (XPC) and hHR23B. The C-terminal domain of centrin (C-HsCen2) binds strongly a peptide from the XPC protein (P1-XPC: N(847)-R(863)). Here, we characterize the solution Ca(2+)-dependent structural and molecular features of the C-HsCen2 in complex with P1-XPC, mainly using NMR spectroscopy and molecular modeling. The N-terminal half of the peptide, organized as an alpha helix is anchored into a deep hydrophobic cavity of the protein, because of three bulky hydrophobic residues in position 1-4-8 and electrostatic contacts with the centrin helix E. Investigation of the whole centrin interactions shows that the N-terminal domain of the protein is not involved in the complex formation and is structurally independent from the peptide-bound C-terminal domain. The complex may exist in three different binding conformations corresponding to zero, one, and two Ca(2+)-bound states, which may exchange with various rates and have distinct structural stability. The various features of the intermolecular interaction presented here constitute a centrin-specific mode for the target binding.
Integrative Imaging Unit, INSERM U759/Institut Curie-Recherche, Centre Universitaire Paris-Sud, Bâtiment 112, 91405 Orsay Cedex, France.